The conventional communication services between mobile terminals (such as call and short message services) depend on an mobile station international public switched telephone network/integrated services digital network number (MSISDN) of the terminal. However, a communication terminal working under machine to machine (M2M) communications cannot depend on an MSISDN for communication because such a terminal does not have an MSISDN.
In the prior art, a scenario where communication is performed without depending on an MSISDN includes a scenario where a server communicates with a terminal having no MSISDN using a short message service (SMS), and a scenario where a terminal having no MSISDN communicates with a terminal having no MSISDN using an SMS.
In the prior art, two terminals can identify each other using a session initiation protocol universal resource identifier (SIP URI) identity; therefore, the two terminals can communicate with each other by transmitting a short message in an Internet Protocol multimedia subsystem (IMS) through the SIP URI-form identity of each other.
However, the inventor finds that, in the prior art, in the process of transmitting a short message, if a short message cannot be stored in the transmission process because a called party cannot receive the current short message, it may result in that the called party cannot receive the short message when the called party is capable of receiving the short message.